The hagen rep said they had a problem with some of the bacteria being too aggressive, and said they'd 'almost completely fixed that' in their newest incarnation of cycle...i.e. they still have no clue whats wrong. And here's something to think about in terms of cycle vs. bio-spira...when we ot the contract to carry bio-spira, marineland included a clause which forced us to bring in new mini-fridges in compliance with their ragulations. A bit extreme, yes, but they've held out on contracts with companies that wouldn't comply,(my old company was one of those, ha dot get it through a backdoor vendor,). Cycle bacteria,(if such a thing actually exists in that bottle,) dies in high temperatures...and I know for a fact I've unloaded trucks where the temp was over 100 degrees fahrenheit and the bottles were hot to the touch, therefore...dead and worthless. Maybe thats the prime cause of bio-spiras failures?